Foam sign

ABSTRACT

A foam sign made from a laminated substrate and several cuts outs die cut from the substrate. The laminated substrate contains a foam layer with a thickness of from about 0.5 to about 3.0 inches, wherein the foam has a density of from about 1.2 to about 2.0 pounds per square foot; the substrate also contains plastic sheets adhesively joined to the top and the bottom of the foam layers, wherein the plastic sheets have a thickness of from about 0.007 to about 0.03 inches; and the laminated substrate also has several cavities designed to receive the cut outs. The cut outs are disposed within such cavities such that the top surfaces of the cut outs are either above or below the top surfaces of the laminated substrate.

REFERENCE TO RELATED PATENT APPLICATION

This patent application is a continuation-in-part of U.S. patentapplication U.S. Ser. No. 09/370,520, filed on Aug. 6, 1999, U.S. Pat.No. 6,129,969.

FIELD OF THE INVENTION

A sign with a laminated foam backing and a multiplicity of laminated cutouts disposed within such backing.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 2,988,835 of Francis S. Murphy discloses a process forproducing a lightweight flat character for a display sign. In theprocess described in this patent, a laminated panel material 10comprising a styrene type plastic foam core 16 which is heat sealed tosheets of kraft paper 17 is die cut. The laminated character thusproduced is taught to be useful for display signs. However, if one wereto attempt to make a sign from the laminated character by pushing itpartially or completely into the foam core from which it was cut, thekraft paper wrinkles and thus presents a poor image.

The Murphy patent does not specify the thickness of its laminated panelmaterial 10, merely stating that it is “ . . . of uniform thickness . .. ” However, it is apparent to those skilled in the art from thedisclosure of the Murphy patent and its drawings that such laminatedpanel material has a thickness of from about 0.06 to about 2 inches. Alaminated character cut from such a panel material does not present asufficiently definite three-dimensional appearance.

The foam characters produced by the process of the Murphy patent couldnot be used to produce signs with attractive three-dimensional effects.For many years, such signs have been produced by using “gatorboard,”which is a styrene foam sheet laminated with white, tan, or black kraftprocess cellulose paper and which is manufactured by the InternationalPaper Company of 6400 Poplar Ave., Memphis, Tenn. This “gatorboard” israther expensive, generally costing about 120 dollars for a 1.5 inchthick 4′×8′ sheet.

When characters are cut out of such “gatorboard,” and then reinsertedinto the area from which they have been cut, there generally is a gap ofat least about 0.12 inches between the characters and the base material.Thus, these characters cannot be friction fit within the recessesproduced in the base material. To produce a sign from such “gatorboard”in which the characters can be friction fit, one must separately machinerecesses within another piece of “gatorboard” which will match thedimensions of the characters machined from the first piece of“gatorboard.” This is a prohibitively expensive process.

One may use a laminated foam panel instead of the “gatorboard” toattempt to produce such three-dimensional signage with friction fitcharacters. However, when the characters are die cut by conventionalmeans from such panel, a substantial amount of the material is fracturedand thus presents a poor appearance as well as poor structuralintegrity.

It is an object of this invention to provide a sign structure whichpresents an attractive three-dimensional affect and which has amultiplicity of laminated characters attached to and disposed within alaminated base.

It is another object of this invention to provide a sign structure whichaffords a cost effective means for providing a wide range of graphiceffects on various surfaces.

It is yet another object of this invention to provide a lightweight,substantially damage-resistant sign structure.

SUMMARY OF THE INVENTION

In accordance with this invention, there is provided a foam signcomprised of a laminated substrate and a multiplicity of laminatedindicia attached to and disposed within such laminated substrate. Thelaminated substrate is comprised of a foam core with a thickness of fromabout 0.5 to about 3.0 inches and a density of from about 1.2 to about 2pounds per cubic foot adhesively attached to two sheets of plastic witha thickness of from about 0.007 to about 0.03 inches; and the indiciacut from such laminated substrate are friction fit and partiallydisposed within the substrate. There is substantially no gap between thesubstrate and the indicia disposed within the substrate.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be described by reference to the following drawings,in which like numerals refer to like elements, and in which:

FIG. 1 is a perspective view of one preferred embodiment of theinvention;

FIG. 2 is an exploded view of the embodiment of FIG. 1;

FIG. 3 is a sectional view, taken along lines 3—3 of FIG. 2, of thesubstrate of the embodiment of FIG. 1;

FIG. 4 is a side view of one aspect of the embodiment of FIG. 1;

FIG. 5 is a side view of another embodiment of the invention;

FIG. 6 is a perspective view of a die cutting machine which may be usedto prepare the foam sign of the invention; and

FIG. 7 is a schematic representation of a preferred die cutting process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a perspective view of a foam sign system 10 that is comprisedof a base 11 comprising a foam substrate material 12, two plastic sheets14 attached to the top and the bottom, respectively, of the foamsubstrate material 12, and a multiplicity of cut outs 13, each of whichis also comprised of a foam substrate material 12 and a plastic sheet 14adhesively attached to the foam substrate material 12. In oneembodiment, foam sign system 10 has a length up to about 6 feet and awidth up to about 5 feet.

The cut outs 13 may be in the shape of letters, figures, words, printeddesigns, trademarks, numerals, regular shapes, irregular shapes, and thelike. Inasmuch as cut outs 13 are produced from base 11, base 11 iscomprised of a series of cavities 15 which are identical in shape to thecut outs 13.

FIG. 1 illustrates the structure 10 which is provided when the cut outs13 are force fitted into the cavities 15. It is noteworthy that, at theinterface 16 of the cut out 13 and the base 11, there is no gap; the cutout 13 fits snugly into the cavity 15 so that a light shining on oneside of the system 10 will not be seen on the other side. If a pin witha diameter of 0.13 inches is inserted at interface 16 and through saidinterface to the back of base 11, it will have to compress either base11 and/or cut out 13 in order to fully extend to the back side of base11.

The snug friction fit between the cut outs 13 and the base 11 alsoguarantees that the cutout will be retained within the base without anyneed for adhesive joining. Inasmuch as the base 11 and the cutouts 13both are the same material, there is a physical and chemical likenessbetween them.

FIG. 3 is a sectional view of the assembly of FIG. 2, taken along lines3—3. Referring to FIG. 3, it will be seen that the foam substratematerial 12 generally has a width 18 of from about 0.5 to about 3.0inches and, more preferably, from about 1 to about 2 inches. In onepreferred embodiment, width 18 is from about 1.4 to about 1.6 inches.

The foam substrate material 12 has a density of from about 1.2 to about2.0 pounds per cubic foot and, more preferably, 1.3 to about 1.8 poundsper cubic foot. In one preferred embodiment, the foam substrate material12 has a density of from about 1.4 to about 1.6 pounds per cubic foot.

In one embodiment, the preferred foam, when evaluated in accordance withthe procedure set forth in A.S.T.M. Standard Test D-3574-91 (1991), hasan indentation force rating of from about 25 to about 50 pounds forceper 50 square inches, a modulus of at least 1.8, a tensile strength ofat least about 12 pounds per square inch, a tear resistance of at leastabout 1.7 pounds per inch thickness, an elongation of at least about 150percent, a compression set (percent loss) of less than 10 percent, and aresilience of at least about 40.

In one preferred embodiment, foam substrate material 12 consistsessentially of polyurethane foam. Thus, by way of illustration and notlimitation, in this embodiment one may use one or more of thepolyurethane foams sold by Valle Foam Industries Inc. of 4 West Drive,Brampton, Ontario as foam grades “1335 RBR,” “1445,” “1540 RBR,” and/or“1338.”

Referring again to FIG. 3, it will be seen that an adhesive 19 joinsfoam layer 12 with plastic sheet 14. Any conventional adhesive and/oradhesive joining means may be used to so join these structures whichdoes not degrade the surface of the foam. Thus, by way of illustration,one may use an adhesive marketed by Adchem Adhesives Inc. of 30Cowansview Road., Cambridge, Ontario as “ADBOND 8706.” This adhesive isa spray grade, non-flammable, fast drying adhesive based upon asynthetic resin/rubber combination, and it is suitable for bondingpolyurethane foam materials. It has a viscosity of from about 280 toabout 320 centipoise, a solids content of from about 28 to about 30weight percent, and a specific gravity of from about 1.23 to about 1.27.

By way of further illustration, another suitable adhesive is “PERMAGRIP107,” which is sold by Imperial Adhesives, Inc. of 6315 Wiehe Road,Cincinnati, Ohio. This adhesive is comprised of from about 40 to about50 weight percent of methylene chloride and from about 30 to about 40weight percent of liquefied petroleum gas propellant.

It is preferred, when adhering the plastic sheets 14 to the foamsubstrate 12, to apply (as by spraying) the adhesive to the surfaces ofboth the plastic sheets and the foam substrate.

Each of the plastic sheets 14 which are preferably affixed to both thetop and bottom of the foam substrate 12, respectively, may comprise onlyone sheet of material. Alternatively, each such plastic sheet 14 maycomprise two or more sheets of material joined together. In eitherevent, the thickness 22 of each such plastic sheet 18 is generallywithin the range of from about 0.007 to about 0.03 inches and, morepreferably, is from about 0.015 to about 0.025 inches. In general, theratio of the thickness 18 of the foam substrate 12 to the thickness 22of each of the plastic layers 14 is at least 15/1 and, preferably, atleast 20/1. In many embodiments, the ratio of the thickness 18 to thethickness 22 is at least about 25/1.

It is preferred that each of the plastic sheets 14 consist essentiallyof a material selected from the group consisting ofacrylonitrile-butadiene-styrene (ABS), polyvinyl chloride, andpolystyrene.

In one embodiment, each of the plastic sheets 14 is a sheet of highimpact polystyrene with a specific gravity of 1.054 to 1.070, a tensilestrength of from about 4,000 to about 10,000 pounds per square inch, anda compressive strength of from about 12,000 to about 17,000 pounds persquare inch.

In one embodiment, each of the plastic sheets 14 is a “silkscreen gradesheet” of polystyrene sold as “Prime Impax 650” by the Primex PlasticsCorproration of 1235 North F Street, Richmond, Ind. This materialpreferably comes in rectangular sheets which are about 40″×72″ and havethicknesses preferably ranging from 0.010 to about 0.125 inches. It ispreferred that the thickness 28 of plastic sheets 14 be from about 0.15to about 0.040 inches.

The plastic sheets 14 preferably are printable. Thus, by way ofillustration, one may use one or more of the printable plastic sheetsdescribed in U.S. Pat. No. 5,891,552 (printable labels), U.S. Pat.No.5,842,722 (printable coplanar laminate), U.S. Pat. Nos. 5,776,604,5,478,629 (printable sheet made from a copolymer of vinyl chloride andvinyl ester), and the like. The disclosure of each of these UnitedStates patents is hereby incorporated by reference into thisspecification.

In one embodiment, each of plastic sheets 14 is comprised of a 0.01clear rigid vinyl substrate bonded to a 0.002 inch brushed silverpolyester.

FIG. 4 is a sectional view of a foam sign assembly 10 in which the cutout 13 is disposed within and above the base 11. In the preferredembodiment depicted, the distance 24 by which cut out 13 extends abovebase 11, is from about 10 to about 90 percent of the thickness 26 of thecut out 13, provided that cut out 13 is disposed to a depth of at leastabout 0.2 inches within base 11. It is even more preferred that thedistance 24 be at least about 0.5 inches and generally is from about 0.5to about 1.2 inches.

Referring again to FIG. 4, and in the preferred embodiment depictedtherein, it will be seen that a spacer 28 is disposed within base 11 andis contiguous with cut out 13; in another embodiment, not shown, thespacer 28 is not contiguous with the cut out 13. The function of spacer28 is to afford some structural integrity to the cut out 13/base 11structure and to help maintain the distance constant. The spacer 28 maybe made of many different materials. Because of cost and weightconsiderations, it is preferred that spacer 28 consist essentially offoam such as, e.g., the same foam used in substrate 12.

The cut out 13 and/or the spacer 28 may be removably attached withinbase 11. Alternatively, with the use of an adhesive (such as, e.g.,adhesive 19), one may permanently attach one or both of such structuresto base 11.

Referring again to FIG. 4, and in the preferred embodiment depictedtherein, it will be seen that a backing 30 is attached to the base 11and the spacer 28 by adhesive means 19.

FIG. 5 illustrates an assembly 10 which is similar to that depicted inFIG. 4 but differs therefrom in having the cut out 13 disposed below thetop surface of base 11 (rather than above it), but not using a spacer28, and by not using a backing 30. In the embodiment depicted in FIG. 5,plastic angle fasteners 32 are adhesively affixed to base 11 and cut out13.

FIG. 6 is a perspective view of a die cutting machine 40 which may beused in the process of this invention. One preferred die cutting machine40 is the “TITAN EM” machine manufactured by Erba & Co., 21052 BustoArsizo, Italy.

Referring to FIG. 6, it will be seen that die cutting machine 40 iscomprised of a controller 42 which is operatively connected to ahydraulic assembly 44. The hydraulic assembly 44 causes lower platen 46to move in the direction of arrow 48 towards upper platen

A steel ruled die 52 is bolted to upper platen 50. In the embodimentdepicted, the die 52 is designed to cut out the word “Storeimage” fromthe base 11. It is essential that, during this process, that the die 52initially contact the foam material 12 instead of the plastic material14. If the die 52 initially contacts the plastic material 14, it willfracture the base 11 and produce cut outs 13 with unacceptableproperties and appearances.

Applicants do not definitively know why the die cutting process workswell when it first contacts the foam material 12 but does not worknearly as well when it first contacts the plastic material 14. It isnoteworthy that, in the process of U.S. Pat. No. 2,988,835, the diefirst contacts kraft paper 17 before it contacts the foam material.

Referring again to FIG. 6, it should be noted that rubber backing 54 ispreferably disposed on every portion of the face of die 52 which is notoccupied by steel rules 56. In one embodiment, steel rules 56 are madefrom hardened steel, have a depth of 0.937 inches, and have a bevelededge.

The presence of the rubber backing 54 tends to urge the cut base 11 awayfrom the steel rules 56 after such rules have cut base 11.

FIG. 7 is a schematic representation of a preferred die cutting process.

In the first step of this process depicted in this FIG. 7, a plasticsheet 14 is attached by means of adhesive 19 to foam 12.

In the second step of the process, which step is optional, a printedgraphic 38 is printed by conventional means onto the plastic sheet 14.Thus, by way of illustration, one may screen print with solvent-based orwater-based ultraviolet inks by conventional means.

Instead of printing a graphic 38 onto the plastic sheet 14, one mayapply other decorative effects such as, e.g., enamel water-based paint,metalized films, holographic patterns, another layer of plasticmaterial, etc.

The base 11 produced by the process up to this point consists of a foammaterial 12 adhesively joined to a plastic material 14 which, in oneembodiment, has one or more graphic displays and/or decorative materialprinted onto or affixed to it. Thereafter, the base 11 is aligned withone or more registration blocks 58, with the foam 12 facing the steelrules 56.

It is preferred not to attach the base 11 to the lower platen 46. Bycomparison, the steel ruled die 52 is preferably bolted to the upperplaten 50 by means of fasteners 60.

In the third step of the process, the cut out 13 and the cut base 11 areremoved from the die cutting machine 40.

In the fourth step of the process, the cut out 13 is inserted intocavity 15 so that it is disposed partially but not completely withinsuch cavity (see FIGS. 4 and 5).

It is to be understood that the aforementioned description isillustrative only and that changes can be made in the apparatus, in theingredients and their proportions, and in the sequence of combinationsand process steps, as well as in other aspects of the inventiondiscussed herein, without departing from the scope of the invention asdefined in the following claims.

We claim:
 1. A foam sign comprised of a laminated substrate and amultiplicity of laminated cut outs attached to and disposed within saidlaminated substrate, wherein: (a) said laminated substrate is comprisedof a first foam substrate with a first top surface and a second topsurface, a first plastic sheet with a third top surface adhesivelyjoined to said first top surface of said first foam substrate, and asecond plastic sheet with a fourth top surface adhesively joined to saidsecond top surface of said first foam substrate, wherein:
 1. said firstfoam substrate has a thickness of from about 0.5 to about 3.0 inches anda density of from about 1.2 to about 2.0 pounds per cubic foot,
 2. saidfirst plastic sheet has a thickness of from about 0.007 to about toabout 0.03 inches,
 3. the ratio of said thickness of said first foamsubstrate to said thickness of said first plastic sheet is at leastabout 15/1,
 4. said second plastic sheet has a thickness of from about0.007 to about to about 0.03 inches, and
 5. the ratio of said thicknessof said first foam substrate to said thickness of said second plasticsheet is at least about 15/1, (b) each of said laminated cut outs iscomprised of a second foam substrate adhesively joined to a thirdplastic sheet with a fifth top surface, wherein:
 1. the foam in saidsecond foam substrate is identical to the foam in said first foamsubstrate,
 2. the thickness of said second foam substrate is identicalto the thickness of said first foam substrate,
 3. the plastic in saidthird plastic sheet is identical to the plastic in said first plasticsheet, and
 4. the thickness of said third plastic sheet is identical tothe thickness of said first plastic sheet, (c) said laminated substrateis comprised of a multiplicity of cavities, and (d) each of saidlaminated cut outs is disposed within one of said cavities such thatthere is a distance between said first top surface of said first plasticsheet and said fifth top surface of said third plastic sheet which isfrom about 10 to about 90 percent of said thickness of said second foamsubstrate, provided that at least about 0.2 inches of said thickness ofsaid laminated cutout is disposed within said cavity.
 2. The foam signas recited in claim 1, wherein each of said cutouts is snugly disposedwithin said laminated substrate such that, when a source of light iscontacted with one surface of said foam sign, it is not perceived at theopposite surface of said foam sign.
 3. The foam sign as recited in claim1, wherein said first foam substrate consists essentially ofpolyurethane foam.
 4. The foam sign as recited in claim 1, wherein saidpolyurethane foam has a density of from about 1.3 to about 1.8 poundsper cubic foot.
 5. The foam sign as recited in claim 4, wherein saidpolyurethane foam has an indentation force rating of from about 25 toabout 50 pounds per 50 square inches, a modulus of at least about 1.8, atensile strength of at least about 12 pounds per square inch, a tearresistance of at least about 1.7 pounds per square inch, an elongationof at least about 150 percent, and a compression set of less than 10percent.
 6. The foam sign as recited in claim 4, wherein said firstplastic sheet is printable.
 7. The foam sign as recited in claim 6,wherein said third top surface of said third plastic sheet is disposedabove said first top surface of said first plastic sheet.
 8. The foamsign as recited in claim 7, wherein a spacer is disposed within saidcavity beneath each of said laminated cut outs.
 9. The foam sign asrecited in claim 8, wherein said spacer is contiguous with saidlaminated cut out.